Use aom_writer with od_laplace_encode_special().

Change the od_laplace_encode_special() function to take an aom_writer
 struct instead of an od_ec_enc struct.
Rename od_laplace_encode_special() to aom_laplace_encode_special().

Change-Id: Ieba63c8519d363081124a11e633b437adccfa500
3 files changed